The best way to contest a speeding ticket is to determine whether the applicable law refers to a basic, presumed or absolute limit and then choose a strategy that targets that law, says Nolo. The best defense for each of these types of laws is different.
An absolute law is used in most states, according to Nolo. The best defenses in these cases are demonstrating that an officer ticketed the wrong vehicle, showing that the speeding occurred to avoid damage or injury to someone, or challenging the methodology used to measure the vehicle's speed. If an officer loses sight of a speeding car, then later pulls over the driver, it can be argued that it was a different car that was speeding. If the speed limit is temporarily exceeded to avoid a road hazard, then speeding may be justified. Officers use pacing, laser and radar guns to measure a vehicle's speed; a good defense is showing that an officer incorrectly used one of these methods.
Contesting a ticket issued under a presumed speed limit law relies on proving that the speed of the vehicle was not unsafe under the circumstances at the time, explains Nolo. If applicable, a defense can use the same strategies used to challenge an absolute law.
States with basic speeding laws allow a ticket to be issued even if a vehicle is going slower than the speed limit, says Nolo. A basic speeding law leaves it up to an officer to determine what is a safe driving speed for any set of road conditions, but unlike absolute and presumed laws, these put the burden of proof on the prosecution.